Mesoscale Discussion 191

Issued

Mar 17, 2021, 1:56 AM CDT (06:56 UTC)

Expired

Mar 17, 2021, 3:00 AM CDT

In force

64 min

Issued by

the Storm Prediction Center

Concerning

Severe thunderstorm watch 22

Counties Blaine County, OK, Custer County, OK, Garfield County, OK, Kay County, OK, Kingfisher County, OK, Logan County, OK, Major County, OK, Noble County, OK, Washita County, OK

The Vance AFB radar (KVNX), 86 km from the middle of the area, began a volume at 06:57 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

727 
ACUS11 KWNS 170657
SWOMCD
SPC MCD 170656 
OKZ000-170800-

Mesoscale Discussion 0191
NWS Storm Prediction Center Norman OK
0156 AM CDT Wed Mar 17 2021

Areas affected...Portions of western/central OK

Concerning...Severe Thunderstorm Watch 22...

Valid 170656Z - 170800Z

The severe weather threat for Severe Thunderstorm Watch 22
continues.

SUMMARY...Mainly a severe hail and wind threat continues across part
of Oklahoma early this morning. Either a watch extension or new
watch may be needed before 08Z (3 AM CDT).

DISCUSSION...Multiple supercells are ongoing as of 0655Z across part
of western/central OK. These mainly elevated storms are ongoing in a
strong low-level warm advection regime, with 40+ kt of
south-southwesterly flow noted in the 0-1 km layer per recent KTLX
VWPs. Large hail should continue to be the main threat, as storms
are tapping into steep mid-level lapse rates noted on the 00Z OUN
sounding. This convection is expected to continue developing
northeastward along an instability gradient, with MUCAPE of
2000-2500+ J/kg available to sustain robust updrafts. Low-level
inflow of around 60F surface dewpoints into these storms appears
marginal for strong/gusty downdraft winds to reach the surface.
Still, given the steep lapse rates aloft and near-neutral boundary
layer stability, isolated strong to severe wind gusts cannot be
ruled out. A brief tornado also appears possible given the very
favorable low-level shear. With Severe Thunderstorm Watch 22
scheduled to expire at 08Z (3 AM CDT) and storms moving fairly
slowly northeastward across north-central OK, either an extension in
time to the ongoing watch or a new watch will likely need to be
considered in the next hour.

..Gleason.. 03/17/2021

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...OUN...

LAT...LON   35159904 35769917 36339853 36819747 36829711 36259706
            36019711 35459833 35159904

Mesoscale Discussions in Oklahoma, 2021Every mesoscale discussion in 2021

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.